[hwasan] Move RunFreeHooks call

Ensures a subsequent call (via an external caller) to
__sanitizer_get_allocated_size via hooks will return a valid size.

This allows a faster version of __sanitizer_get_allocated_size
to be implemented, which can skip checks.

Test to ensure RunFreeHooks' call order will come with
__sanitizer_get_allocated_size_fast

Differential Revision: https://reviews.llvm.org/D151151